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Phycomyces: a change in mechanical properties after a light stimulus
J K Ortega1, R I Gamow, C N Ahlquist
1Department of Aerospace Engineering Sciences and Mechanical Engineering Department, University of Colorado, Boulder, Colorado 80302.
Plant Physiology
|February 1, 1975
Summary
Light exposure increases the mechanical extensibility of the fungal cell wall in Phycomyces sporangiophores. This change, crucial for growth, is localized in the growing zone beneath the sporangium.
Area of Science:
- Plant biology
- Mycology
- Biophysics
Background:
- The fungus Phycomyces exhibits phototropism, a growth response to light.
- Understanding cell wall mechanics is vital for explaining fungal growth dynamics.
Purpose of the Study:
- To investigate the effect of light stimulus on the mechanical extensibility of the Phycomyces sporangiophore cell wall.
Main Methods:
- Tensile tests were performed on stage IVb sporangiophores.
- Tests were conducted both before and after a saturating light stimulus.
Main Results:
- A significant increase in mechanical extensibility was observed post-light stimulus.
- This enhanced extensibility was localized to the growing zone of the sporangiophore.
- The majority of the increase occurred approximately 300 micrometers below the sporangium.
Conclusions:
- Light stimulus alters the mechanical properties of the Phycomyces sporangiophore cell wall.
- This light-induced change in extensibility likely plays a role in the fungus's phototropic growth response.
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